Do physical therapists follow evidence-based practices for treatment of inflammatory arthritis? Results from an online survey

BACKGROUND

Physical therapists (PTs) should know how to best treat patients with inflammatory arthritis.

OBJECTIVE

To document interventions chosen by PTs for patients with rheumatoid arthritis (RA) and ankylosing spondylitis (AS) and whether choices follow evidence-based practice.

METHODS

Licensed musculoskeletal PTs in Quebec, Canada responded to an online survey. Descriptive statistics illustrated proportions for each treatment choice and inferential statistics explored associations with demographic and practice-related factors.

RESULTS

There were 298 PTs who responded to the survey. For both RA and AS respectively, most common interventions were mobility exercises (91.0%; 98.3%) and patient education (90.1%; 92.8%). For both cases, slightly >60% selected strengthening exercises. Passive forms of therapy were chosen by 36% of PTs for RA and 58% for AS. Aerobic exercise was rarely selected. PTs working in the public sector were less likely to use manual therapy for both RA (Odds Ratio (OR) 0.43, 95% confidence interval (CI) 0.22,0.86) and AS (OR 0.46, 95% CI 0.22,0.97).

CONCLUSIONS

Most PTs chose mobility exercises and patient education, representing evidence-based approaches. Despite current recommendations, strengthening and especially aerobic exercises were not used as much. There is a need to increase awareness regarding the benefits of strengthening and aerobic exercise for these patients.

Measuring the impact of an educational intervention in rheumatoid arthritis: An open-label, randomized trial

Objectives

This study aims to determine whether patients with active rheumatoid arthritis (RA), either starting on or changing biological or targeted synthetic disease-modifying antirheumatic drugs (DMARDs), demonstrate better self-management safety skills three months after receiving a multidisciplinary educational intervention compared to patients receiving usual care.

Patients and methods

Between October 2015 and October 2018 , this open-label, randomized-controlled trial included a total of 107 RA patients (27 males, 80 females; mean age: 60.2±10.4 years; range, 54 to 71 years) who were on treatment or in whom treatment was changed with a biological or targeted synthetic DMARD. The patients were randomized into two groups: Group 1 (n=57) received additional intervention with educational DVD and one teleconference session and Group 2 (n=55) received usual care and were offered the intervention at three months. All patients underwent a final visit at six months. At each visit, the patients completed the BioSecure questionnaire measuring the self-care safety skills, a behavioral intention questionnaire, and the Beliefs about Medicines Questionnaire (BMQ).

Results

No significant difference was observed in the Biosecure score at three months between the two groups (p=0.08). After pooling the first three-month data in Group 1 and the last three-month data in Group 2, the mean score of the BioSecure questionnaire increased to 7.10±0.92 in the group receiving educational intervention (p<0.0001). This increase was maintained at six months in Group 2 (p=0.88). The rate of appropriate behavioral intention increased over time (76% at baseline and 85% at six months for both groups). There was no significant change in the BMQ (p=0.44 to 0.84).

Conclusion

The development of an educational DVD followed by a teleconference seem to improve self-care safety skills of the patients in practical situations.

Expectations and educational needs of rheumatologists, rheumatology fellows and patients in the field of precision medicine in Canada, a quantitative cross-sectional and descriptive study

Background

Precision medicine, as a personalized medicine approach based on biomarkers, is a booming field. In general, physicians and patients have a positive attitude toward precision medicine, but their knowledge and experience are limited. In this study, we aimed at assessing the expectations and educational needs for precision medicine among rheumatologists, rheumatology fellows and patients with rheumatic diseases in Canada.

Methods

We conducted two anonymous online surveys between June and August 2018, one with rheumatologists and fellows and one with patients assessing precision medicine expectations and educational needs. Descriptive statistics were performed.

Results

45 rheumatologists, 6 fellows and 277 patients answered the survey. 78% of rheumatologists and fellows and 97.1% of patients would like to receive training on precision medicine. Most rheumatologists and fellows agreed that precision medicine tests are relevant to medical practice (73.5%) with benefits such as helping to determine prognosis (58.9%), diagnosis (79.4%) and avoid treatment toxicity (61.8%). They are less convinced of their usefulness in helping to choose the most effective treatment and to improve patient adherence (23.5%). Most patients were eager to take precision medicine tests that could predict disease prognosis (92.4%), treatment response (98.1%) or drug toxicity (93.4%), but they feared potential negative impacts like loss of insurability (62.2%) and high cost of the test (57.5%).

Conclusions

Our study showed that rheumatologists and patients in Canada are overall interested in getting additional precision medicine education. Indeed, while convinced of the potential benefits of precision medicine tests, most physicians don’t feel confident in their abilities and consider their training insufficient to incorporate them into clinical practice.

Supplementary Information

The online version contains supplementary material available at 10.1186/s41927-021-00222-2.

Application of Artificial Intelligence in Community-Based Primary Health Care: Systematic Scoping Review and Critical Appraisal

BACKGROUND

Research on the integration of artificial intelligence (AI) into community-based primary health care (CBPHC) has highlighted several advantages and disadvantages in practice regarding, for example, facilitating diagnosis and disease management, as well as doubts concerning the unintended harmful effects of this integration. However, there is a lack of evidence about a comprehensive knowledge synthesis that could shed light on AI systems tested or implemented in CBPHC.

OBJECTIVE

We intended to identify and evaluate published studies that have tested or implemented AI in CBPHC settings.

METHODS

We conducted a systematic scoping review informed by an earlier study and the Joanna Briggs Institute (JBI) scoping review framework and reported the findings according to PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analysis-Scoping Reviews) reporting guidelines. An information specialist performed a comprehensive search from the date of inception until February 2020, in seven bibliographic databases: Cochrane Library, MEDLINE, EMBASE, Web of Science, Cumulative Index to Nursing and Allied Health Literature (CINAHL), ScienceDirect, and IEEE Xplore. The selected studies considered all populations who provide and receive care in CBPHC settings, AI interventions that had been implemented, tested, or both, and assessed outcomes related to patients, health care providers, or CBPHC systems. Risk of bias was assessed using the Prediction Model Risk of Bias Assessment Tool (PROBAST). Two authors independently screened the titles and abstracts of the identified records, read the selected full texts, and extracted data from the included studies using a validated extraction form. Disagreements were resolved by consensus, and if this was not possible, the opinion of a third reviewer was sought. A third reviewer also validated all the extracted data.

RESULTS

We retrieved 22,113 documents. After the removal of duplicates, 16,870 documents were screened, and 90 peer-reviewed publications met our inclusion criteria. Machine learning (ML) (41/90, 45%), natural language processing (NLP) (24/90, 27%), and expert systems (17/90, 19%) were the most commonly studied AI interventions. These were primarily implemented for diagnosis, detection, or surveillance purposes. Neural networks (ie, convolutional neural networks and abductive networks) demonstrated the highest accuracy, considering the given database for the given clinical task. The risk of bias in diagnosis or prognosis studies was the lowest in the participant category (4/49, 4%) and the highest in the outcome category (22/49, 45%).

CONCLUSIONS

We observed variabilities in reporting the participants, types of AI methods, analyses, and outcomes, and highlighted the large gap in the effective development and implementation of AI in CBPHC. Further studies are needed to efficiently guide the development and implementation of AI interventions in CBPHC settings.

Twelve Lessons Learned for Effective Research Partnerships Between Patients, Caregivers, Clinicians, Academic Researchers, and Other Stakeholders

Research increasingly means that patients, caregivers, health professionals, other stakeholders, and academic investigators work in partnership. This requires effective collaboration rooted in mutual respect, involvement of all participants, and good communication. Having conducted such partnered research over multiple projects, and having recently completed a project together funded by the Patient-Centered Outcomes Research Institute, we collaboratively developed a list of 12 lessons we have learned about how to ensure effective research partnerships. To foster a culture of mutual respect, hold early in-person meetings, with introductions focused on motivation, offer appropriate orientation for everyone, and maintain awareness of individual and project goals. To actively involve all team members, it is important to ensure sufficient funding for everyone's participation, to ask for and recognize diverse contributions, and to seek the input of quiet members. To facilitate good communication, teams should carefully consider labels, avoid jargon and acronyms, judiciously use homogeneous and heterogeneous subgroups, and keep progress visible. In offering pragmatic, actionable lessons we have learned through our separate and shared experiences, we hope to help foster more patient-centered research via productive and enjoyable research collaborations.

Involving members of vulnerable populations in the development of patient decision aids: a mixed methods sequential explanatory study

Background

Patient decision aids aim to present evidence relevant to a health decision in understandable ways to support patients through the process of making evidence-informed, values-congruent health decisions. It is recommended that, when developing these tools, teams involve people who may ultimately use them. However, there is little empirical evidence about how best to undertake this involvement, particularly for specific populations of users such as vulnerable populations.

Methods

To describe and compare the development practices of research teams that did and did not specifically involve members of vulnerable populations in the development of patient decision aids, we conducted a secondary analysis of data from a systematic review about the development processes of patient decision aids. Then, to further explain our quantitative results, we conducted semi-structured telephone interviews with 10 teams: 6 that had specifically involved members of vulnerable populations and 4 that had not. Two independent analysts thematically coded transcribed interviews.

Results

Out of a total of 187 decision aid development projects, 30 (16%) specifically involved members of vulnerable populations. The specific involvement of members of vulnerable populations in the development process was associated with conducting informal needs assessment activities (73% vs. 40%, OR 2.96, 95% CI 1.18–7.99, P = .02) and recruiting participants through community-based organizations (40% vs. 11%, OR 3.48, 95% CI 1.23–9.83, P = .02). In interviews, all developers highlighted the importance, value and challenges of involving potential users. Interviews with developers whose projects had involved members of vulnerable populations suggested that informal needs assessment activities served to center the decision aid around users’ needs, to better avoid stigma, and to ensure that the topic truly matters to the community. Partnering with community-based organizations may facilitate relationships of trust and may also provide a non-threatening and accessible location for research activities.

Conclusions

There are a small number of key differences in the development processes for patient decision aids in which members of vulnerable populations were or were not specifically involved. Some of these practices may require additional time or resources. To address health inequities, researchers, communities and funders may need to increase awareness of these approaches and plan accordingly.

Electronic supplementary material

The online version of this article (doi:10.1186/s12911-016-0399-8) contains supplementary material, which is available to authorized users.

User-centered design and the development of patient decision aids: protocol for a systematic review

BACKGROUND

Providing patient-centered care requires that patients partner in their personal health-care decisions to the full extent desired. Patient decision aids facilitate processes of shared decision-making between patients and their clinicians by presenting relevant scientific information in balanced, understandable ways, helping clarify patients' goals, and guiding decision-making processes. Although international standards stipulate that patients and clinicians should be involved in decision aid development, little is known about how such involvement currently occurs, let alone best practices. This systematic review consisting of three interlinked subreviews seeks to describe current practices of user involvement in the development of patient decision aids, compare these to practices of user-centered design, and identify promising strategies.

METHODS/DESIGN

A research team that includes patient and clinician representatives, decision aid developers, and systematic review method experts will guide this review according to the Cochrane Handbook and PRISMA reporting guidelines. A medical librarian will hand search key references and use a peer-reviewed search strategy to search MEDLINE, EMBASE, PubMed, Web of Science, the Cochrane Library, the ACM library, IEEE Xplore, and Google Scholar. We will identify articles across all languages and years describing the development or evaluation of a patient decision aid, or the application of user-centered design or human-centered design to tools intended for patient use. Two independent reviewers will assess article eligibility and extract data into a matrix using a structured pilot-tested form based on a conceptual framework of user-centered design. We will synthesize evidence to describe how research teams have included users in their development process and compare these practices to user-centered design methods. If data permit, we will develop a measure of the user-centeredness of development processes and identify practices that are likely to be optimal.

DISCUSSION

This systematic review will provide evidence of current practices to inform approaches for involving patients and other stakeholders in the development of patient decision aids. We anticipate that the results will help move towards the establishment of best practices for the development of patient-centered tools and, in turn, help improve the experiences of people who face difficult health decisions.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42014013241.

Rheumatoid arthritis pharmacotherapy and predictors of disease-modifying anti-rheumatic drug initiation in the early years of biologic use in Quebec, Canada

Disease-modifying anti-rheumatic drugs (DMARDs) are the cornerstone of rheumatoid arthritis (RA) pharmacotherapy and should be initiated promptly after RA diagnosis. We examined trends in use of traditional and biologic DMARDs, and non-DMARD treatments, among overall RA patients, and factors associated with DMARD initiation in the newly diagnosed RA. RA subjects identified with the Quebec administrative databases were followed between January 1, 2002, and December 31, 2008. DMARD use was characterized on November 1 of each year using cross-sectional analyses. For a subgroup of newly diagnosed subjects, we used multivariable logistic regressions to identify predictors of DMARD initiation within 12 months of diagnosis and survival analyses to appraise time to DMARD initiation. A total of 37,399 subjects were included (65.8 % ≥65 years; 70.5 % female). The percentage of subjects using any DMARDs increased over the study period from 41.4 % [95 % confidence interval (CI) 40.8-42.0] to 43.3 % (95 % CI 42.7-43.9). Among newly diagnosed RA, being followed by a rheumatologist was the strongest predictor of DMARD initiation (odds ratio 4.31; 95 % CI 3.73-4.97). Care by an internist, increasing calendar year, use of NSAIDs, corticosteroids, or opioids, and a history of hospitalization increased the likelihood of DMARD initiation. Older age, female, higher comorbidity score, number of medical visits pre-diagnosis, care by other specialists, and the use of acetaminophen were inversely associated with DMARD initiation. The probability of any DMARD initiation at 12 months was 38.5 %. Despite the clinical practice guideline recommendations for earlier aggressive RA management, DMARD use appears to be suboptimal in Quebec.

Core competencies for shared decision making training programs: insights from an international, interdisciplinary working group

Shared decision making is now making inroads in health care professionals' continuing education curriculum, but there is no consensus on what core competencies are required by clinicians for effectively involving patients in health-related decisions. Ready-made programs for training clinicians in shared decision making are in high demand, but existing programs vary widely in their theoretical foundations, length, and content. An international, interdisciplinary group of 25 individuals met in 2012 to discuss theoretical approaches to making health-related decisions, compare notes on existing programs, take stock of stakeholders concerns, and deliberate on core competencies. This article summarizes the results of those discussions. Some participants believed that existing models already provide a sufficient conceptual basis for developing and implementing shared decision making competency-based training programs on a wide scale. Others argued that this would be premature as there is still no consensus on the definition of shared decision making or sufficient evidence to recommend specific competencies for implementing shared decision making. However, all participants agreed that there were 2 broad types of competencies that clinicians need for implementing shared decision making: relational competencies and risk communication competencies. Further multidisciplinary research could broaden and deepen our understanding of core competencies for shared decision making training.

Canadian Rheumatology Association recommendations for the pharmacological management of rheumatoid arthritis with traditional and biologic disease-modifying antirheumatic drugs: part II safety

OBJECTIVE

The Canadian Rheumatology Association (CRA) has developed recommendations for the pharmacological management of rheumatoid arthritis (RA) with traditional and biologic disease-modifying antirheumatic drugs (DMARD) in 2 parts. Part II, focusing on specific safety aspects of treatment with traditional and biologic DMARD in patients with RA, is reported here.

METHODS

Key questions were identified a priori based on results of a national needs-assessment survey. A systematic review of all clinical practice guidelines and consensus statements regarding treatment with traditional and biologic DMARD in patients with RA published between January 2000 and June 2010 was performed in Medline, Embase, and CINAHL databases, and was supplemented with a "grey literature" search including relevant public health guidelines. Systematic reviews of postmarketing surveillance and RA registry studies were performed to update included guideline literature reviews as appropriate. Guideline quality was independently assessed by 2 reviewers. Guideline characteristics, recommendations, and supporting evidence from observational studies and randomized trials were synthesized into evidence tables. The working group voted on recommendations using a modified Delphi technique.

RESULTS

Thirteen recommendations addressing perioperative care, screening for latent tuberculosis infection prior to the initiation of biologic DMARD, optimal vaccination practices, and treatment of RA patients with active or a history of malignancy were developed for rheumatologists, other primary prescribers of RA drug therapies, and RA patients.

CONCLUSION

These recommendations were developed based on a synthesis of international RA and public health guidelines, supporting evidence, and expert consensus in the context of the Canadian health system. They are intended to help promote best practices and improve healthcare delivery for persons with RA.

Patient and Public Involvement in Clinical Practice Guidelines

Background. The role of patient and public involvement programs (PPIPs) in developing and implementing clinical practice guidelines (CPGs) has generated great interest. Purpose. The authors sought to identify key components of PPIPs used in developing and implementing CPGs. Data sources. The authors searched bibliographic databases and contacted relevant organizations. Study selection. In total, 2161 articles and reports were retrieved on PPIPs in the development and implementation of CPGs. Of these, 71 qualified for inclusion in the review. Data extraction. Reviewers independently extracted data on key components of PPIPs and barriers and facilitators to their operation. Data synthesis. Over half of the studies were published after 2002, and more than half originated from the United States, the United Kingdom, Australia, and Germany. CPGs that involved patients and the public addressed a variety of health problems, especially mental health and cancer. The most frequently cited objective for using PPIPs in developing CPGs was to incorporate patients’ values or perspectives in CPG recommendations. Patients and their families and caregivers were the parties most often involved. Methods used to recruit PPIP participants included soliciting through patient/public organizations, sending invitations, and receiving referrals and recruits from clinicians. Patients and the public most often participated by taking part in a CPG working group, workshop, meeting, seminar, literature review, or consultation such as a focus group, individual interview, or survey. Patients and the public principally helped formulate recommendations and revise drafts. Limitations. The authors did not contact the authors of the studies. Conclusion. This literature review provides an extensive knowledge base for making PPIPs more effective when developing and implementing CPGs. More research is needed to assess the impact of PPIPs and resources they require.

Canadian Rheumatology Association recommendations for pharmacological management of rheumatoid arthritis with traditional and biologic disease-modifying antirheumatic drugs

OBJECTIVE

The Canadian Rheumatology Association (CRA) has developed recommendations for the pharmacological management of rheumatoid arthritis (RA) with traditional and biologic disease-modifying antirheumatic drugs (DMARD) in 2 parts. Part 1 is reported here.

METHODS

The CRA Therapeutics Committee assembled a national working group of RA clinical experts, researchers, patient consumers, and a general practitioner. Treatment questions were developed a priori based on results of a national needs assessment survey. A systematic review of all clinical practice guidelines and consensus statements regarding treatment with traditional and biologic DMARD in patients with RA published between January 2000 and June 2010 was performed in Medline, Embase, and CINAHL databases, and the grey literature. Guideline quality was assessed by 2 independent reviewers, and guideline characteristics, recommendations, and supporting evidence from observational studies and randomized controlled trials were synthesized into evidence tables. The full working group reviewed the evidence tables and developed recommendations using a modified Delphi technique.

RESULTS

Five overarching principles and 26 recommendations addressing general RA management strategies and treatment with glucocorticoids and traditional and biologic DMARD were developed for rheumatologists, other primary prescribers of RA drug therapies, and patients with RA.

CONCLUSION

These recommendations were developed based on a synthesis of international guidelines, supporting evidence, and expert consensus considering the Canadian healthcare context with the intention of promoting best practices and improving healthcare delivery for persons with RA.

Living at home or in an institution: what makes the difference for seniors?

OBJECTIVES

This article examines some of the health and socio-demographic factors associated with living in long-term health care facilities rather than in private households, for elderly people with various levels of disability.

DATA SOURCE

The data are from the 1996/97 National Population Health Survey conducted by Statistics Canada. Data from a sample of 1,711 people aged 65 or older living in long-term health care facilities and 13,363 in private households were weighted to represent about 185,100 and 3.4 million seniors, respectively.

ANALYTICAL TECHNIQUES

Descriptive data were produced using bivariate frequencies. Multiple logistic regression models were used to examine associations between living in long-term health care facilities and selected health and socio-demographic characteristics for seniors with self-reported severe, moderate or no disability.

MAIN RESULTS

While health status was strongly associated with residence in a long-term health care facility, the absence of a spouse, low income, low education, and advanced age were also significant.

Human sex ratio at birth and mother's birth season: multivariate analysis

We used a population-based historical French Canadian database to examine the effects of mother's birth season on sex ratio at birth. Non-first births in the database (n = 127,658) were analyzed for their sex, parish size (2 large parishes of Montreal and Quebec or the other smaller parishes), time period (births up to 1719 or those from 1720), maternal age (< or = 24, 25-29, 30-34, 35+ years), sex of the preceding sibling (male or female), and birth seasons of the child and his or her parents (February-April, May-July, August-October, November-January). Season of child's birth significantly affected the sex ratio (chi 2 = 11.507, d.f. = 3, p = 0.009), with the births in February-April or May-July showing a lower sex ratio. Season of mother's birth also contributed highly significantly to the variation of sex ratio (chi 2 = 15.196, d.f. = 3, p = 0.002); mothers born in February-April had a low sex ratio among their children (sex ratio = 1.013). In contrast, season of father's birth did not affect the sex ratio (chi 2 = 0.618, d.f. = 3, p = 0.892). When a multiple logistic model was applied to the data, mother's birth season was the single most significant factor. The lower sex ratio from mothers born in February-April was observed consistently for every maternal age and delivery season. Seasonal influences on female fetuses seem to have changed their future reproductive characteristics.

Practice guidelines for clinical prevention: do patients, physicians and experts share common ground?

BACKGROUND

Clinical practice guidelines, such as those of the Canadian Task Force on Preventive Health Care, although based on sound evidence, may conflict with the perceived needs and expectations of patients and physicians. This may jeopardize the implementation of such guidelines. This study was undertaken to explore patients' and family physicians' acceptance of the task force's recommendations and the values and criteria upon which the opinions of these 2 groups are based.

METHODS

Focus groups were used to collect study data. In total, 35 physicians (in 7 groups) and 75 patient representatives (in 9 groups) participated in the focus groups. An inductive approach was used to develop coding grids and to generate themes from the transcripts of the interviews.

RESULTS

Physicians expressed resistance to discontinuing the annual check-up, which they viewed as an organizational strategy to counteract the many barriers to preventive care that they encounter. They reported difficulties in explaining to their patients the recommendations of the Canadian Task Force on Preventive Health Care, which they found complex and inconsistent with popular wisdom. Both patients and physicians attributed high value to the detection of insidious diseases, even in the absence of proof of the effectiveness of such activity.

INTERPRETATION

The patients and family physicians who participated in this study shared many opinions on the value of preventive activities that depart from the values used by "prevention experts" such as the Canadian Task Force on Preventive Health Care in establishing their recommendations. A better understanding of the values of patients and physicians would help guideline developers to create better targeted communication strategies to take these discrepancies into account.

Marriage season, promptness of successful pregnancy and first-born sex ratio in a historical natural fertility population--evidence for sex-dependent early pregnancy loss?

We investigated population-based vital records of the seventeenth and eighteenth century French Canadian population to assess the effects of marriage season on the outcome of the first births under natural fertility conditions (n = 21,698 marriages). Promptness of the first successful conception after marriage differed according to marriage season; the proportion of marriages with a marriage-first birth interval of 8.0-10.0 months was lowest (34%) for marriages in August-October (P = 0.001). Although the male/female sex ratio of the babies born with an interval of 8.0-10.0 months was generally higher (1.10) than those with an interval of 10.0-24.0 months (1.05), the marriages in August-October resulted in a significantly reduced sex ratio (0.96) among only the prompt conceptions (P = 0.026). We discuss whether this seasonal reduction of the sex ratio could be partly explained by a clustered pregnancy loss of male zygotes in early pregnancy.

A cohort approach to tobacco use and mortality: the case of Quebec

BACKGROUND

Cigarette smoking is the No. 1 cause of premature death among Canadians. However, tobacco consumption dropped by 35% in Canada during the 1980s.

METHODS

Using data collected during a Quebec health survey, we evaluated the prevalences of tobacco use by birth cohort. Since mortality has been decreasing for both sexes, we computed gender-specific cohort mortality indices for tobacco-related causes of death. In the analysis, we took into account the inevitable time lag between adopting the behavior and becoming the victim of a smoking-attributable disease.

RESULTS

Results indicate a systematic decrease in tobacco use from older male cohorts to younger ones across all ages; however, for females an increase in tobacco use has been observed from one cohort to the next but there seems to be hope for a future trend toward breaking the habit. While a decline in tobacco-related mortality has been observed among men (e.g., death from ischemic heart disease), female lung cancer mortality increased considerably. Finally, we present an indicator measuring the years of potential life lost for some tobacco-related causes of death.

CONCLUSIONS

The cohort approach allows us to observe birth-cohort-specific trends, thereby more easily relating past behavior to current mortality levels. In terms of prevention, increasing female mortality from lung cancer should become a major concern and a motivator in the fight against tobacco use.

Slow twin conception at first birth and subsequent maternal twin proneness in a natural fertility population

To study whether apparently more fecund women having delivered twins at first birth have traits of higher twin-proneness, we performed a retrospective cohort study on population-based historical vital records of the 17-18th century French Canadian immigrants and their descendants under natural fertility conditions. Among 24896 mothers who had at least one child, 248 had twin maternities at their first birth (twinning rate = 1.0%). Among 21508 mothers with a valid marriage-first birth interval, twinning rate was 0.97% among prompt conceptions (7.0-11.0 months), with a particularly high rate at the interval of 7.0-8.0 months (2.2%). Marriages in August-October resulted in a higher twinning rate particularly for the slow conceptions than those in the other seasons. Promptly-conceived mothers of twins at the first delivery may seem to have higher fecundity, but subsequent births from these mothers (n = 88) show a lower twinning rate (1.7%) particularly at younger maternal age than from the other mothers who had slowly conceived twins at their first birth (n = 112). The latter show a 4.5% twinning rate as a whole among their second or later births. So-called twin-proneness of a mother, whether genetic or acquired, was not connected to higher conception rate of twin's mothers immediately after marriage. Reduced fecundity, which may have been imposed by some environmental factors, could raise the chance of twinning.

Reproductive life of French-Canadians in the 17-18th centuries: a search for a trade-off between early fecundity and longevity

One of the predictions derived from Williams' (1957) evolutionary theory of senescence is the existence of a trade-off between early fecundity and longevity. The population register of the French immigrants to Québec in the 17th century and of the first Canadians in the 17th and 18th centuries was used to detect such a trade-off in a noncontraceptive human population living at a time when longevity had not been prolonged by medical care and was not artificially shortened by wars, epidemics, or other external causes. No evidence for such a trade-off could be detected in these populations which had not yet reached the demographic transition phase (i.e., the historical period when longevity began to be extended and the progeny began to be reduced). Results are discussed in connection with the various studies aiming to test the Williams' theory.

Effects of maternal birth season on birth seasonality in the Canadian population during the seventeenth and eighteenth centuries

Birth records of the French-Canadian population for the period 1621-1765 were analyzed retrospectively to examine the effect of maternal birth season on the seasonal distribution of births. Preliminary examination indicated that there was a bimodal pattern in birth seasonality: a major peak in early spring, a trough in early summer, a minor peak in autumn, and a trough around December. Because this seasonality was strongly biased at the level of the first birth by the month of marriage, which was concentrated in November, the seasonality of nonfirst births (n = 32,926) was examined in relation to the four seasons of maternal birth. Mothers born in May-July showed a flatter monthly distribution of nonfirst births at a maternal age of 28 years or more. Analysis of marriage-first birth intervals indicated that mothers who married in August-October showed a lower percentage of immediate conception (intervals of 8-10 months), whereas those mothers born in May-July had a higher percentage of immediate conception. This difference in birth seasonality shown by mothers born in May-July is similar to results from early twentieth-century Japan. Some seasonal infertility factors could have affected the embryos at the earliest stage of pregnancy, modifying a part of the seasonal variation in birth rate.